Try Kukui Trail. This path begins at a short nature loop featuring native plants of which are neatly labeled for your knowledge needs! There is a nice lookout point too.
The continues for 2.5 miles and drops over 2,000ft to the bottom of Waimea Canyon! There are numerous outstanding vista points as you descend
The final miles within forest and finishes at Waimea River where you can take a nice swim if you like. It's 2,000ft back to the top and very difficult. For most people we recommend doing HALF the trail. Swim at the beach!
Secrets Beach up in north shore is one the most incredible beaches on island. It's a nearly half mile walk down a semi steep trail to the bottom where true Polynesia is layed out before your eyes. From here, you can walk the entire beach and jump in the water anytime you like. If you hike to the end this whole journey will be about two miles.
This is a beach you'll want to linger at so bring towels, sunscreen and a nice snack. Beach chairs are great too especially if they have straps so you can backpack them in. Leave the snorkel gear in car and be careful with waves, especially in the winter!
The Kuilau Trail on the eastside of Kauai is perhaps the most underated trail in Kauai. It begins with a 1.25 mile gradual incline through lush jungle. A great lookout point with picnic tables is at the top of this ridge.
The trail continues and winds along a tiny ridge that nature could not have designed any better. Here you are above the rainforest canopy and it's awesome.
You'll reach a small waterfall and bridge which connects Kuilau Trail with Moalepe Trail. It's worth continuing if you have the energy. In all, each trail is about 2 miles in length so if you do the entire thing it's about 8 roundtrip.
If you have two cars we love hiking the entire thing one way and driving back. Another pro tip, from Kuilau, don't miss the nearby Rainbow forest and take a dip in it's exotic swim holes!
Kauai has zillions of waterfalls but accessing them is tricky to recommend. Wailua Falls, Opaeka Falls are both possible but dangerous to hike too. And illegal. We've done it but we can't tell you how and for that we apologize. Hoopii Falls is possible but it's heavily used and in a residential area and we also do not recommend it.
The easiest and best option is the trail to secret falls. It's only accessible by kayak so either rent them or take a tour. The River Kayak and waterfall hike activity can be found on the link below.
The Kapa'a Bike Path is a splendid, paved and level 6 mile coastal trail that is great for everyone. You can walk or bike it and it feautures none stop coastal views and will pass several beaches.
Our favorite portion is between Kealia Beach and Donkey Beach. This portion sits a little higher on the sea cliffs and you can really feel the power of the ocean. It's great for whale watching during the winter. This portion is about 1.5 miles each way and there is public access to both beaches.
The Sleeping Giant (Nounou) in Kapaa features 3 unique trails that take you all the way to the top of a beautiful lookout sporting views of the entire eastside of Kauai.
We recommend "West" route. It's the shortest route and you get the most bang for your buck. You'll find the link below.
Avid hikers should do the longer ones if you're game. The trail starting on the Wailua Houselots "East" trail is especially good as you get all the nice views as you ascend.
The "Kuamo'o East" trail is the longest and follows the base of Sleeping Giant for a mile or before linking up With the shorter East Trail. It's mostly forest views though there is a nice lookout early on!